Method of manufacture for microelectromechanical devices

- IDC, LLC

A method of manufacturing a microelectromechanical device includes forming at least two conductive layers on a substrate. An isolation layer is formed between the two conductive layers. The conductive layers are electrically coupled together and then the isolation layer is removed to form a gap between the conductive layers. The electrical coupling of the layers mitigates or eliminates the effects of electrostatic charge build up on the device during the removal process.

Skip to: Description  ·  Claims  ·  References Cited  · Patent History  ·  Patent History
Description
BACKGROUND

Microelectromechanical system devices (MEMS) may be manufactured from thin film processes. These processes may involve a series of thin films deposited in layers, the layers being patterned and etched to form the devices. In order to allow the devices to move, one layer may be an isolation layer. An isolation layer is one that is used in forming the layers of the device acting as a structural member, but that may be removed when the device is complete.

Removal of the isolation layers may involve an etching process, using a material as the etchant that only acts on the sacrificial layer material. In some cases, the isolation layer may be an oxide that may be removed with a dry gas etch. Other forms of isolation layers are also possible, as are other methods of removal. The removal of the isolation layer typically results in a gap, through which a member of the device will move upon actuation.

MEMS devices often actuate through the use of electrical signals that cause a voltage differential between a first conductive layer and a second conductive layer separated by the gap. During dry, gas etching of the isolation layer, an electrostatic charge may build up on the layers, causing the movable member to become attracted to the other conductive layer. In extreme cases, the two layers may become stuck together and the device becomes inoperative. In less extreme cases, the movable element may become damages or deformed and subsequently not operate correctly.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention may be best understood by reading the disclosure with reference to the drawings, wherein:

FIG. 1 shows an embodiment of a microelectromechanical device formed using an isolation layer.

FIG. 2 shows an embodiment of a microelectromechanical device rendered inoperable by a static charge buildup during an etch process.

FIG. 3 shows an embodiment of an apparatus to mitigate the effects of static charge buildup during an etch process.

FIG. 4 shows an alternative embodiment of an apparatus to mitigate the effects of static charge during an etch process.

FIG. 5 shows a flowchart of an embodiment of a method to manufacture a microelectromechanical device.

FIGS. 6a and 6b show embodiments of an alternative apparatus to mitigate the effects of static charge during an etch process.

 DETAILED DESCRIPTION OF THE EMBODIMENTS

FIG. 1 shows an example of a microelectromechanical device that is formed from thin film processes including an isolation layer. This particular example is of an interferometric modulator, but embodiments of the invention may be applicable to all kinds of MEMS devices that are formed from thin film processes with an isolation layer. The modulator is formed on a transparent substrate 10. An optical stack typically comprising layers of metal and oxides such as 12 and 14 is formed upon the substrate 10. A metal membrane 18 is formed upon a sacrificial layer, not shown. The sacrificial layer may also be referred to as an isolation layer, as it acts to electrically isolate conductive layers from each other during processing. Prior to the formation of the membrane, vias are patterned into the isolation layer to allow metal from the membrane to fill in the vias and form posts, such as 16.

Upon completion of the modulator structures, such as the metal membrane 18, the isolation layer is removed. This allows portions of the membrane 18 to deflect towards the electrode layer 12 of the optical stack. In the case of interferometric modulators, the membrane 18 is attracted to the metal layer 12 by manipulation of the voltage differential between the membrane 18 and the electrode layer 12. The layer 12 and the membrane 18 may be metal, as discussed here, or any conductive material. The cell formed by the portion of the membrane shown in FIG. 1 is activated by applying a voltage to the conductive layer 14, which differs from the voltage of the membrane at 18. This causes the membrane to become electrostatically attracted to the electrode, or first conductive, layer 12. The conductive layers may be metal or any other conductive material.

During removal of the isolation layer, enough electrostatic charge can build up on the surfaces of the two conductive layers to cause the membrane to attract towards the conductive layer 14 without being activated. This condition is shown in FIG. 2. This is normally the activated state of the interferometric modulator, but the difference is that the membrane does not release from the oxide layer 12 upon changing of the voltage potential. The membrane has assumed the activated state permanently. This may be caused by a combination sticking and friction, often referred to as stiction, aggravated by the electrostatic forces between the conductive layer 12 and the conductive membrane 18.

Removal of the isolation layer may be achieved in many different ways. Typically, it is removed with the use of a dry, gas etch, such as a xenon-difluorine (XeF2) etch. While these are examples of etching processes, any etch process may be used. It may be the dry environment that contributes to the build up of the electrostatic charge. However, it would be better to not have to change the materials or basis of the processes used to manufacture the MEMS devices, but instead to adapt the process to eliminate the electrostatic charge build up.

There are some benefits to be obtained by grounding the conductive layers during wet etch processes as well. There may be effects on the device electrochemistry that are either enabled, if desirable, or mitigated, if undesirable, by grounding. In one embodiment, the layers are grounded together, the isolation layers are removed and the grounding left in place so the devices can be safely transported without fear of electrostatic discharge. This would be helpful if the etch were a wet etch or a dry etch.

The grounding process may be an external grounding, by an apparatus or mechanism external to the structure of the device. Alternatively, the grounding may be as part of the internal structure of the device enabled during manufacture. Initially, external grounding will be discussed.

An apparatus for mitigating the build up of electrostatic charge during etching processes is shown in FIG. 3. An alternative embodiment is shown in FIG. 4. In FIG. 3, a conductive wire 22 has been attached to the first and second conductive layers 14 and 18 to hold them at the same potential. The same potential could involve attaching them to a ground plane, or just attaching them together. By holding them at the same potential, the electrostatic charge build up will not cause a differential between the two layers, and will therefore avoid the problem of having the membrane actuate during the etch process. As will be discussed in more detail further, this will typically be done just prior to the etch process, although the two layers could be electrically coupled together at any point prior to the etch process. It may be desirable to restrict the electrical coupling to the inactive area of the substrates upon which the devices are manufactured.

The alternative embodiment of FIG. 4 shows a device being manufactured out of three conductive layers and two isolation layers. In this embodiment of an interferometric modulator, the equivalent to the second conductive layer 18 in FIGS. 1 and 3 is actually two conductive layers 18a and 18b. They are generally deposited as two separate layers but are in physical or electrical connection with each other. This will typically result in the combination of the flex layer and the mirror layer only requiring one connection to be connecting with the other conductive layers. This particular formation may require two isolation layers as the equivalent of the first isolation layer, because a isolation layer may be formed between the layers 18a and 18b in addition to the one formed between layer 18a and the electrode layer 12. The connection between layers 18a and 18b may be formed by a via in the second portion of the first isolation layer. For purposes of discussion here, this isolation layer is not of interest in that the conductive layer deposited upon does not generally need a conductive wire to connect it to the other conductive layers.

A second isolation layer 25 may be formed on the flex layer 18b, to provide a separation between the conductive layer 18b and a third conductive layer 26. The third conductive layer in this example is the bus layer, used to form a signaling bus above the flex and mirror layers to aid in addressing of the cells of the modulator. Regardless of the application or the MEMS device in which embodiments of the invention may be employed, this is just intended as an example of multiple conductive layers being electrically coupled to mitigate or eliminate the electrostatic charge build up during the etch process.

Also shown in FIG. 4 is an alternative to a connection between the two layers alone. In FIG. 24, the conductive wire 22 is attached to a ground plane, in this example the frame of the etch chamber 30. This may be more desirable than having the two or more layers electrically connected together, as they will be to a ‘known’ potential, that is ground. Alternatively, the conductive wires 22 and 24 could be attached to other structures. As long as the two or more layers are held at the same potential, the build up of electrostatic charge should not cause the membrane to be attracted to the conductive layer on the substrate.

As mentioned previously, it is probably more desirable to use a means of avoiding or mitigating electrostatic charge build up that does not interfere with current process flows for manufacturing of MEMS devices. An example of a method of manufacturing a MEMS device, in this case the interferometric modulator mentioned previously, is shown in flowchart form in FIG. 5.

It must be noted that the process flow given as a particular example in this discussion is for an interferometric modulator. However, embodiments of this invention may be applied to any MEMS device manufacturing flow having isolation layers removed by dry, gas etching. As discussed previously, the interferometric modulator is built upon a transparent substrate such as glass. An electrode layer is deposited, patterned and etched at 32 to form electrodes for addressing the cells of the modulator. The optical layer is then deposited and etched at 34. The first isolation layer is deposited at 36, then the mirror layer at 38. In this example, the first conductive layer will be the mirror layer.

The first conductive layer is then patterned and etched at 40. A second isolation layer is deposited at 42. Again, this is specific to the example of FIG. 4, in which the second conductive layer is actually formed from two conductive layers, the flex layer and the mirror layer. The first and second isolation layers may be treated as one isolation layer, as the electrostatic charge buildup between the conductive layers on either side of the second isolation layer is not a concern. The flex layer is then deposited at 44, and patterned and etched at 46.

At 48, the typical process flow is altered to include the grounding of the first and second conductive layers, in this case the electrode layer and the mirror/flex layer. For a device having two conductive layers and one effective isolation layer, the process may end at 50, with the isolation layer being removed with an etch. This is only one embodiment, and the ending of the process is therefore shown in a dashed box. For a device having more than two conductive layers, the process may instead continue at 52.

At 52 a third isolation layer is deposited at 52 in this particular example. As discussed above, this may actually be only a second, effective isolation layer. The bus layer, or third conductive layer, is deposited at 54, patterned and etched at 56. At 58, the conductive layers, in this example there are three, are grounded or electrically coupled together at 58, and the isolation layers are removed at 60. Depending upon the functionality of the device and the electrical drive scheme, the conductive layers may be decoupled at 62. For the example of the interferometric modulator, where the operation of the device relies upon the electrostatic attraction arising between conductive layers being held at different voltage potentials, the coupling would have to be removed.

The wire coupling is an example of an external process of coupling the conductive layers. Other external examples include using test probe structures to provide coupling between the layers, and the use of an ionized gas, where the molecules of the gas itself provides coupling between the layers.

It must be noted that the process of connecting the layers together, or connecting them all to the same potential is referred to as coupling the layers. This is intended to cover the situations in which the layers are just connected together, connected together to a common potential where that potential includes ground, or connected individually to a common or same potential. No restriction on how the layers are electrically coupled together is in intended.

An example of an internal grounding apparatus is shown in FIGS. 6a and 6b. As part of the manufacture of the MEMS devices, typically many devices are manufactured on one substrate, a portion of which is shown at 70 in FIG. 6a. During manufacture of the device, leads may be provided from the various layers, such as the electrode layer 12, the mechanical or mirror layer 18, and the bussing layer 26, of the device to test pads or tabs such as 76. It is possible to couple these pads together, such as by connection 74 that ties all of the pads together, as part of the conductive layer patterning and etching processes of manufacturing the devices. This would couple the conductive layers together for further processing.

As mentioned above, for devices that cannot operate with the layers coupled together, this internal coupling would have to be removed. As shown in FIG. 6b, the connections between the pads 76 and the coupling connection 74 could be broken. When the substrate is divided up into its individual devices, it may be sawn, scribed, or otherwise broken. The lines used to form the breaks, such as the scribe line 78, would sever the coupling between the pads 76 and the coupling connection 74. This is an example of internal coupling.

In this manner, MEMS devices having conductive layers and at least one isolation layer can be etched using current processes while avoiding electrostatic charge build up that may render the devices inoperable. Prior to packaging, and typically upon removal of the device from the etch chamber, the connections are removed or otherwise eliminated from the devices.

Thus, although there has been described to this point a particular embodiment for a method and apparatus for mitigating or eliminating the effects of electrostatic charge during etch processes, it is not intended that such specific references be considered as limitations upon the scope of this invention except in-so-far as set forth in the following claims.

Claims

1. A method of manufacturing a microelectromechanical device, comprising:

forming at least a first and a second conductive layer on a substrate;
forming an isolation layer between the two conductive layers;
electrically coupling the conductive layers together using a solid conductor to provide electrical connection to the conductive layers;
removing the isolation layer to form a gap between the first conductive layer and the second conductive layer; and
electrically decoupling the conductive layers after removing the isolation layer.

2. The method of claim 1, further comprising forming a third conductive layer.

3. The method of claim 2, wherein forming an isolation layer further comprises forming two isolation layers.

4. The method of claim 1, wherein removing the isolation layer comprises performing an etch of the isolation layer.

5. The method of claim 4, wherein performing an etch comprises performing a dry gas etch.

6. The method of claim 5, wherein performing a dry gas etch comprises performing a xenon-difluorine etch.

7. The method of claim 1, wherein electrically coupling the conductive layers together comprises coupling the conductive layers together using an external coupling.

8. The method of claim 1, wherein electrically coupling comprises electrically coupling the conductive layers together during fabrication of at least a portion of the MEMS device.

9. The method of claim 1, wherein electrically coupling the conductive layers together comprises coupling the conductive layers together by forming one or more coupling connections over the substrate.

10. The method of claim 1, wherein electrically coupling the conductive layers together comprises using a conductive wire to provide electrical connection to the conductive layers.

11. The method of claim 1, wherein electrically coupling the conductive layers together comprises using a conductive wire to provide electrical connection to the conductive layers and then connecting the wire to a common voltage potential.

12. The method of claim I, wherein electrically coupling the conductive layers together comprises using conductive wires for each conductive layer and electrically connecting all of the wires to the same potential.

13. The method of claim 1, wherein electrically coupling the conductive layers together comprises electrically coupling the conductive layers together in an inactive area of the substrate.

14. The method of claim 1, wherein electrically decoupling the conductive layers comprises physically separating a conductive lead between the conductive layers.

Referenced Cited
U.S. Patent Documents
2534846 December 1950 Ambrose et al.
3296530 January 1967 Brooks
3439973 April 1969 Paul et al.
3443854 May 1969 Weiss
3653741 April 1972 Marks
3656836 April 1972 de Cremoux et al.
3725868 April 1973 Malmer, Jr. et al.
3813265 May 1974 Marks
3955880 May 11, 1976 Lierke
4099854 July 11, 1978 Decker et al.
4196396 April 1, 1980 Smith
4228437 October 14, 1980 Shelton
4377324 March 22, 1983 Durand et al.
4389096 June 21, 1983 Hori et al.
4392711 July 12, 1983 Moraw et al.
4403248 September 6, 1983 te Velde
4441791 April 10, 1984 Hornbeck
4445050 April 24, 1984 Marks
4459182 July 10, 1984 te Velde
4482213 November 13, 1984 Piliavin et al.
4500171 February 19, 1985 Penz et al.
4519676 May 28, 1985 te Velde
4531126 July 23, 1985 Sadones
4566935 January 28, 1986 Hornbeck
4571603 February 18, 1986 Hornbeck et al.
4596992 June 24, 1986 Hornbeck
4615595 October 7, 1986 Hornbeck
4662746 May 5, 1987 Hornbeck
4663083 May 5, 1987 Marks
4666254 May 19, 1987 Itoh et al.
4681403 July 21, 1987 te Velde et al.
4710732 December 1, 1987 Hornbeck
4748366 May 31, 1988 Taylor
4786128 November 22, 1988 Birnbach
4790635 December 13, 1988 Apsley
4856863 August 15, 1989 Sampsell et al.
4857978 August 15, 1989 Goldburt et al.
4859060 August 22, 1989 Katagiri et al.
4900136 February 13, 1990 Goldburt et al.
4900395 February 13, 1990 Syverson et al.
4937496 June 26, 1990 Neiger et al.
4954789 September 4, 1990 Sampsell
4956619 September 11, 1990 Hornbeck
4965562 October 23, 1990 Verhulst
4982184 January 1, 1991 Kirkwood
5018256 May 28, 1991 Hornbeck
5022745 June 11, 1991 Zahowski et al.
5028939 July 2, 1991 Hornbeck et al.
5037173 August 6, 1991 Sampsell et al.
5044736 September 3, 1991 Jaskie et al.
5061049 October 29, 1991 Hornbeck
5075796 December 24, 1991 Schildkraut et al.
5078479 January 7, 1992 Vuilleumier
5079544 January 7, 1992 DeMond et al.
5083857 January 28, 1992 Hornbeck
5096279 March 17, 1992 Hornbeck et al.
5099353 March 24, 1992 Hornbeck
5124834 June 23, 1992 Cusano et al.
5136669 August 4, 1992 Gerdt
5142405 August 25, 1992 Hornbeck
5142414 August 25, 1992 Koehler
5153771 October 6, 1992 Link et al.
5162787 November 10, 1992 Thompson et al.
5168406 December 1, 1992 Nelson
5170156 December 8, 1992 DeMond et al.
5172262 December 15, 1992 Hornbeck
5179274 January 12, 1993 Sampsell
5192395 March 9, 1993 Boysel et al.
5192946 March 9, 1993 Thompson et al.
5206629 April 27, 1993 DeMond et al.
5212582 May 18, 1993 Nelson
5214419 May 25, 1993 DeMond et al.
5214420 May 25, 1993 Thompson et al.
5216537 June 1, 1993 Hornbeck
5226099 July 6, 1993 Mignardi et al.
5228013 July 13, 1993 Bik
5231532 July 27, 1993 Magel et al.
5233385 August 3, 1993 Sampsell
5233456 August 3, 1993 Nelson
5233459 August 3, 1993 Bozler et al.
5254980 October 19, 1993 Hendrix et al.
5272473 December 21, 1993 Thompson et al.
5278652 January 11, 1994 Urbanus et al.
5280277 January 18, 1994 Hornbeck
5287096 February 15, 1994 Thompson et al.
5293272 March 8, 1994 Jannson et al.
5296950 March 22, 1994 Lin et al.
5305640 April 26, 1994 Boysel et al.
5311360 May 10, 1994 Bloom et al.
5312513 May 17, 1994 Florence et al.
5323002 June 21, 1994 Sampsell et al.
5324683 June 28, 1994 Fitch et al.
5325116 June 28, 1994 Sampsell
5326430 July 5, 1994 Cronin et al.
5327286 July 5, 1994 Sampsell et al.
5331454 July 19, 1994 Hornbeck
5339116 August 16, 1994 Urbanus et al.
5345328 September 6, 1994 Fritz et al.
5355357 October 11, 1994 Yamamori et al.
5358601 October 25, 1994 Cathey
5365283 November 15, 1994 Doherty et al.
5381232 January 10, 1995 Van Wijk
5381253 January 10, 1995 Sharp et al.
5401983 March 28, 1995 Jokerst et al.
5411769 May 2, 1995 Hornbeck
5444566 August 22, 1995 Gale et al.
5446479 August 29, 1995 Thompson et al.
5448314 September 5, 1995 Heimbuch et al.
5452024 September 19, 1995 Sampsell
5454906 October 3, 1995 Baker et al.
5457493 October 10, 1995 Leddy et al.
5457566 October 10, 1995 Sampsell et al.
5459602 October 17, 1995 Sampsell
5459610 October 17, 1995 Bloom et al.
5461411 October 24, 1995 Florence et al.
5474865 December 12, 1995 Vasudev
5489952 February 6, 1996 Gove et al.
5497172 March 5, 1996 Doherty et al.
5497197 March 5, 1996 Gove et al.
5499037 March 12, 1996 Nakagawa et al.
5499062 March 12, 1996 Urbanus
5500635 March 19, 1996 Mott
5500761 March 19, 1996 Goossen et al.
5506597 April 9, 1996 Thompson et al.
5515076 May 7, 1996 Thompson et al.
5517347 May 14, 1996 Sampsell
5523803 June 4, 1996 Urbanus et al.
5526051 June 11, 1996 Gove et al.
5526172 June 11, 1996 Kanack
5526327 June 11, 1996 Cordova, Jr.
5526688 June 18, 1996 Boysel et al.
5535047 July 9, 1996 Hornbeck
5548301 August 20, 1996 Kornher et al.
5551293 September 3, 1996 Boysel et al.
5552924 September 3, 1996 Tregilgas
5552925 September 3, 1996 Worley
5559358 September 24, 1996 Burns et al.
5563398 October 8, 1996 Sampsell
5567334 October 22, 1996 Baker et al.
5570135 October 29, 1996 Gove et al.
5579149 November 26, 1996 Moret et al.
5581272 December 3, 1996 Conner et al.
5583688 December 10, 1996 Hornbeck
5589852 December 31, 1996 Thompson et al.
5597736 January 28, 1997 Sampsell
5600383 February 4, 1997 Hornbeck
5602671 February 11, 1997 Hornbeck
5606441 February 25, 1997 Florence et al.
5608468 March 4, 1997 Gove et al.
5610438 March 11, 1997 Wallace et al.
5610624 March 11, 1997 Bhuva
5610625 March 11, 1997 Sampsell
5614937 March 25, 1997 Nelson
5619059 April 8, 1997 Li et al.
5619061 April 8, 1997 Goldsmith et al.
5619365 April 8, 1997 Rhoads et al.
5619366 April 8, 1997 Rhoads et al.
5629790 May 13, 1997 Neukermans et al.
5633652 May 27, 1997 Kanbe et al.
5636052 June 3, 1997 Arney et al.
5636185 June 3, 1997 Brewer et al.
5638084 June 10, 1997 Kalt
5638946 June 17, 1997 Zavracky
5641391 June 24, 1997 Hunter et al.
5646768 July 8, 1997 Kaeriyama
5650881 July 22, 1997 Hornbeck
5654741 August 5, 1997 Sampsell et al.
5657099 August 12, 1997 Doherty et al.
5659374 August 19, 1997 Gale, Jr. et al.
5661591 August 26, 1997 Lin et al.
5665997 September 9, 1997 Weaver et al.
5673139 September 30, 1997 Johnson
5683591 November 4, 1997 Offenberg
5703710 December 30, 1997 Brinkman et al.
5710656 January 20, 1998 Goosen
5726480 March 10, 1998 Pister
5739945 April 14, 1998 Tayebati
5740150 April 14, 1998 Uchimaru et al.
5745193 April 28, 1998 Urbanus et al.
5745281 April 28, 1998 Yi et al.
5751469 May 12, 1998 Arney et al.
5771116 June 23, 1998 Miller et al.
5784190 July 21, 1998 Worley
5784212 July 21, 1998 Hornbeck
5786927 July 28, 1998 Greywall et al.
5793504 August 11, 1998 Stoll
5808780 September 15, 1998 McDonald
5808781 September 15, 1998 Arney et al.
5818095 October 6, 1998 Sampsell
5825528 October 20, 1998 Goosen
5835255 November 10, 1998 Miles
5838484 November 17, 1998 Goossen et al.
5842088 November 24, 1998 Thompson
5867302 February 2, 1999 Fleming
5905482 May 18, 1999 Hughes et al.
5912758 June 15, 1999 Knipe et al.
5943158 August 24, 1999 Ford et al.
5959763 September 28, 1999 Bozler et al.
5986796 November 16, 1999 Miles
5994174 November 30, 1999 Carey et al.
6028690 February 22, 2000 Carter et al.
6038056 March 14, 2000 Florence et al.
6040937 March 21, 2000 Miles
6046840 April 4, 2000 Huibers
6049317 April 11, 2000 Thompson et al.
6055090 April 25, 2000 Miles
6056406 May 2, 2000 Park et al.
6061075 May 9, 2000 Nelson et al.
6097145 August 1, 2000 Kastalsky et al.
6099132 August 8, 2000 Kaeriyama
6100872 August 8, 2000 Aratani et al.
6113239 September 5, 2000 Sampsell et al.
6115014 September 5, 2000 Aoki et al.
6147790 November 14, 2000 Meier et al.
6158156 December 12, 2000 Patrick
6160833 December 12, 2000 Floyd et al.
6171945 January 9, 2001 Mandal et al.
6172797 January 9, 2001 Huibers
6180428 January 30, 2001 Peeters et al.
6195196 February 27, 2001 Kimura et al.
6201633 March 13, 2001 Peeters et al.
6215221 April 10, 2001 Cabuz et al.
6232936 May 15, 2001 Gove et al.
6239777 May 29, 2001 Sugahara et al.
6243149 June 5, 2001 Swanson et al.
6282010 August 28, 2001 Sulzbach et al.
6288472 September 11, 2001 Cabuz et al.
6288824 September 11, 2001 Kastalsky
6295154 September 25, 2001 Laor et al.
6316289 November 13, 2001 Chung
6323982 November 27, 2001 Hornbeck
6327071 December 4, 2001 Kimura
6331909 December 18, 2001 Dunfield
6335831 January 1, 2002 Kowarz et al.
6356254 March 12, 2002 Kimura
6356378 March 12, 2002 Huibers
6358021 March 19, 2002 Cabuz
6376787 April 23, 2002 Martin et al.
6407851 June 18, 2002 Islam et al.
6417868 July 9, 2002 Bock et al.
6438282 August 20, 2002 Takeda et al.
6447126 September 10, 2002 Hornbeck
6449084 September 10, 2002 Guo
6456420 September 24, 2002 Goodwin-Johansson
6465355 October 15, 2002 Horsley
6466190 October 15, 2002 Evoy
6466354 October 15, 2002 Gudeman
6466358 October 15, 2002 Tew
6473072 October 29, 2002 Comiskey et al.
6473274 October 29, 2002 Maimone et al.
6480177 November 12, 2002 Doherty et al.
6496122 December 17, 2002 Sampsell
6545335 April 8, 2003 Chua et al.
6548908 April 15, 2003 Chua et al.
6549338 April 15, 2003 Wolverton et al.
6552840 April 22, 2003 Knipe
6574033 June 3, 2003 Chui et al.
6589625 July 8, 2003 Kothari et al.
6600201 July 29, 2003 Hartwell et al.
6606175 August 12, 2003 Sampsell et al.
6607935 August 19, 2003 Kwon
6608268 August 19, 2003 Goldsmith
6624944 September 23, 2003 Wallace et al.
6625047 September 23, 2003 Coleman, Jr.
6630786 October 7, 2003 Cummings et al.
6632698 October 14, 2003 Ives
6635919 October 21, 2003 Melendez et al.
6643069 November 4, 2003 Dewald
6650455 November 18, 2003 Miles
6657832 December 2, 2003 Williams et al.
6660656 December 9, 2003 Cheung et al.
6666561 December 23, 2003 Blakley
6674090 January 6, 2004 Chua et al.
6674562 January 6, 2004 Miles et al.
6674563 January 6, 2004 Chui et al.
6680792 January 20, 2004 Miles
6707355 March 16, 2004 Yee
6710908 March 23, 2004 Miles et al.
6741377 May 25, 2004 Miles
6741383 May 25, 2004 Huibers et al.
6741384 May 25, 2004 Martin et al.
6741503 May 25, 2004 Farris et al.
6747785 June 8, 2004 Chen et al.
6747800 June 8, 2004 Lin
6775174 August 10, 2004 Huffman et al.
6778155 August 17, 2004 Doherty et al.
6794119 September 21, 2004 Miles
6809788 October 26, 2004 Yamada et al.
6811267 November 2, 2004 Allen et al.
6819469 November 16, 2004 Koba
6822628 November 23, 2004 Dunphy et al.
6829132 December 7, 2004 Martin et al.
6841081 January 11, 2005 Chang et al.
6853129 February 8, 2005 Cummings et al.
6855610 February 15, 2005 Tung et al.
6859218 February 22, 2005 Luman et al.
6861277 March 1, 2005 Monroe et al.
6862022 March 1, 2005 Slupe
6862029 March 1, 2005 D'Souza et al.
6867896 March 15, 2005 Miles
6870581 March 22, 2005 Li et al.
6870654 March 22, 2005 Lin et al.
6882458 April 19, 2005 Lin et al.
6882461 April 19, 2005 Tsai et al.
6891658 May 10, 2005 Whitehead et al.
6912022 June 28, 2005 Lin et al.
6917268 July 12, 2005 Deligianni et al.
6947200 September 20, 2005 Huibers
6952303 October 4, 2005 Lin et al.
6958847 October 25, 2005 Lin
6959990 November 1, 2005 Penn
7008812 March 7, 2006 Carley
7053737 May 30, 2006 Schwartz et al.
7075700 July 11, 2006 Muenter
7123216 October 17, 2006 Miles
7236284 June 26, 2007 Miles
7372613 May 13, 2008 Chui et al.
20010003487 June 14, 2001 Miles
20010028503 October 11, 2001 Flanders et al.
20020014579 February 7, 2002 Dunfield
20020015215 February 7, 2002 Miles
20020021485 February 21, 2002 Pilossof
20020024711 February 28, 2002 Miles
20020027636 March 7, 2002 Yamada
20020054424 May 9, 2002 Miles
20020075555 June 20, 2002 Miles
20020114558 August 22, 2002 Nemirovsky
20020126364 September 12, 2002 Miles
20020139981 October 3, 2002 Young
20020146200 October 10, 2002 Kurdle et al.
20020149828 October 17, 2002 Miles
20020149850 October 17, 2002 Heffner et al.
20020167072 November 14, 2002 Andosca
20020167730 November 14, 2002 Needham et al.
20020186483 December 12, 2002 Hagelin et al.
20030015936 January 23, 2003 Yoon et al.
20030016428 January 23, 2003 Kato et al.
20030029705 February 13, 2003 Qui et al.
20030043157 March 6, 2003 Miles
20030053078 March 20, 2003 Missey et al.
20030072070 April 17, 2003 Miles
20030156315 August 21, 2003 Li et al.
20030202264 October 30, 2003 Weber et al.
20030202265 October 30, 2003 Reboa et al.
20030202266 October 30, 2003 Ring et al.
20030210851 November 13, 2003 Fu et al.
20040008396 January 15, 2004 Stappaerts
20040008438 January 15, 2004 Sato
20040027671 February 12, 2004 Wu et al.
20040027701 February 12, 2004 Ishikawa
20040051929 March 18, 2004 Sampsell et al.
20040056742 March 25, 2004 Dabbaj
20040058532 March 25, 2004 Miles et al.
20040075967 April 22, 2004 Lynch et al.
20040080035 April 29, 2004 Delapierre
20040080807 April 29, 2004 Chen et al.
20040100594 May 27, 2004 Huibers et al.
20040100680 May 27, 2004 Huibers et al.
20040124483 July 1, 2004 Partridge et al.
20040125281 July 1, 2004 Lin
20040125347 July 1, 2004 Patel et al.
20040136045 July 15, 2004 Tran
20040140557 July 22, 2004 Sun et al.
20040145049 July 29, 2004 McKinnell et al.
20040145811 July 29, 2004 Lin et al.
20040147056 July 29, 2004 McKinnell et al.
20040147198 July 29, 2004 Lin et al.
20040148009 July 29, 2004 Buzzard et al.
20040150939 August 5, 2004 Huff
20040160143 August 19, 2004 Shreeve et al.
20040174583 September 9, 2004 Chen et al.
20040175577 September 9, 2004 Lin et al.
20040179281 September 16, 2004 Reboa
20040179445 September 16, 2004 Park et al.
20040184766 September 23, 2004 Kim et al.
20040201908 October 14, 2004 Kaneko
20040207897 October 21, 2004 Lin
20040209192 October 21, 2004 Lin et al.
20040209195 October 21, 2004 Lin
20040212026 October 28, 2004 Van Brocklin et al.
20040217378 November 4, 2004 Martin et al.
20040217919 November 4, 2004 Pichl et al.
20040218251 November 4, 2004 Piehl et al.
20040218334 November 4, 2004 Martin et al.
20040218341 November 4, 2004 Martin et al.
20040227493 November 18, 2004 Van Brocklin et al.
20040233503 November 25, 2004 Kimura
20040240032 December 2, 2004 Miles
20040240138 December 2, 2004 Martin et al.
20040245588 December 9, 2004 Nikkel et al.
20040263944 December 30, 2004 Miles et al.
20050001828 January 6, 2005 Martin et al.
20050002082 January 6, 2005 Miles
20050003667 January 6, 2005 Lin et al.
20050014374 January 20, 2005 Partridge et al.
20050024557 February 3, 2005 Lin
20050035699 February 17, 2005 Tsai
20050036095 February 17, 2005 Yeh et al.
20050036192 February 17, 2005 Lin et al.
20050038950 February 17, 2005 Adelmann
20050042117 February 24, 2005 Lin
20050046922 March 3, 2005 Lin et al.
20050046948 March 3, 2005 Lin
20050057442 March 17, 2005 Way
20050068583 March 31, 2005 Gutkowski et al.
20050068605 March 31, 2005 Tsai
20050068606 March 31, 2005 Tsai
20050069209 March 31, 2005 Damera-Venkata et al.
20050078348 April 14, 2005 Lin
20050157364 July 21, 2005 Lin
20050168849 August 4, 2005 Lin
20050195462 September 8, 2005 Lin
20050195467 September 8, 2005 Kothari et al.
20050202649 September 15, 2005 Hung et al.
20050239275 October 27, 2005 Muthukumar et al.
20060022966 February 2, 2006 Mar
20060044654 March 2, 2006 Vandorpe et al.
20060066935 March 30, 2006 Cummings et al.
20060077533 April 13, 2006 Miles et al.
20060139723 June 29, 2006 Miles et al.
20070008607 January 11, 2007 Miles
20070229936 October 4, 2007 Miles
20080055705 March 6, 2008 Kothari
Foreign Patent Documents
4108966 September 1992 DE
10228946 January 2004 DE
0 310 176 April 1989 EP
0 361 981 April 1990 EP
0 667 548 August 1995 EP
0 788 005 August 1997 EP
1275997 January 2003 EP
1 435 336 July 2004 EP
1 473 691 November 2004 EP
1473581 November 2004 EP
1484635 December 2004 EP
2 824 643 November 2002 FR
62 082454 April 1987 JP
04-276721 October 1992 JP
05275401 October 1993 JP
9-127439 May 1997 JP
11211999 August 1999 JP
11211999 November 1999 JP
2000306515 November 2000 JP
2002-062490 February 2002 JP
2002277771 September 2002 JP
2003-195201 July 2003 JP
2003195201 July 2003 JP
2004157527 June 2004 JP
2004235465 August 2004 JP
2004286825 October 2004 JP
157313 May 1991 TW
WO9530924 November 1995 WO
WO9717628 May 1997 WO
WO9952006 October 1999 WO
WO9952006 October 1999 WO
WO 02/079853 October 2002 WO
WO03007049 January 2003 WO
WO 03/014789 February 2003 WO
2003/054925 July 2003 WO
WO 03/054925 July 2003 WO
2003/069413 August 2003 WO
WO 03/069404 August 2003 WO
WO03069413 August 2003 WO
WO03073151 September 2003 WO
WO 03/085728 October 2003 WO
WO04006003 January 2004 WO
WO04026757 April 2004 WO
WO 2005/006364 January 2005 WO
WO 2006/014929 February 2006 WO
Other references
  • Akasaka, “Three Dimensional IC Trends”, Proceedings of IEEE, vol. 74, No. 12, pp. 1703-1714, (Dec. 1986).
  • Aratani et al., “Process and Design Considerations for Surface Micromachined Beams for a Tuneable Interferometer Array in Silicon,” Proc. IEEE Microelectromechanical Workshop, Fort Lauderdale, FL, pp. 230-235 (Feb. 1993).
  • Aratani K., et al., “Surface micromachined tuneable interferometer array,” Sensors and Actuators, pp. 17-23. (1994).
  • Bass, “Handbook of Optics, vol. I, Fundamentals, Techniques, and Design, Second Edition,” McGraw-Hill, Inc., New York, pp. 2.29-2.36 (1995).
  • Conner, “Hybrid Color Display Using Optical Interference Filter Array,” SID Digest, pp. 577-580 (1993).
  • Giles et al., “A Silicon MEMS Optical Switch Attenuator and Its Use in Lightwave Subsystems,” IEEE Journal of Selected Topics in Quanum Electronics, vol. 5, No. 1, pp. 18-25, (Jan./Feb. 1999).
  • Goossen et al., “Possible Display Applications of the Silicon Mechanical Anti-Reflection Switch,” Society for Information Display (1994).
  • Goossen et al., “Silicon Modulator Based on Mechanically-Active Anti-Reflection Layer with 1Mbit/sec Capability for Fiber-in-the-Loop Applications,” IEEE Photonics Technology Letters, pp. 1119, 1121 (Sep. 1994).
  • Gosch, “West Germany Grabs the Lead in X-Ray Lithography,” Electronics pp. 78-80 (Feb. 5, 1987).
  • Howard et al., “Nanometer-Scale Fabrication Techniques”, VLSI Electronics: Microstructure Science, vol. 5, pp. 143-153 and pp. 166-173 (1982).
  • Ibbotson et al., “Comparison of XeF2 and F-atom reactions with Si and SiO2,” Applied Physics Letters, vol. 44, No. 12, pp. 1129-1131 (Jun. 1984).
  • Jackson “Classical Electrodynamics”, John Wiley & Sons Inc., pp. 568-573. (date unknown).
  • Jerman et al., “A Miniature Fabry-Perot Interferometer with a Corrugated Silicon Diaphragm Support”, (1988).
  • Johnson “Optical Scanners”, Microwave Scanning Antennas, vol. 1, p. 251-261, (1964).
  • Light over Matter, Circle No. 36 (Jun. 1993).
  • Miles, Mark, W., “A New Reflective FPD Technology Using Interferometric Modulation”, The Proceedings of the Society for Information Display (May 11-16, 1997).
  • Newsbreaks, “Quantum-trench devices might operate at terahertz frequencies”, Laser Focus World (May 1993).
  • Oliner et al., “Radiating Elements and Mutual Coupling”, Microwave Scanning Antennas, vol. 2, pp. 131-141, (1966).
  • Raley et al., “A Fabry-Perot Microinterferometer for Visible Wavelengths”, IEEE Solid-State Sensor and Actuator Workshop, Jun. 1992, Hilton Head, SC.
  • Schnakenberg, et al. TMAHW Etchants for Silicon Micromachining. 1991 International Conference on Solid State Sensors and Actuators-Digest of Technical Papers. pp. 815-818.
  • Sperger et al., “High Performance Patterned All-Dielectric Interference Colour Filter for Display Applications”, SID Digest, pp. 81-83, (1994).
  • Stone, “Radiation and Optics, An Introduction to the Classical Theory”, McGraw-Hill, pp. 340-343, (1963).
  • Walker, et al., “Electron-beam-tunable Interference Filter Spatial Light Modulator”, Optics Letters vol. 13, No. 5, pp. 345-347, (May 1988).
  • Williams, et al. Etch Rates for Micromachining Processing. Journal of Microelectromechanical Systems, vol. 5, No. 4, pp. 256-259, (Dec. 1996).
  • Winters, et al. The etching of silicon with XeF2 vapor. Applied Physics Letters, vol. 34, No. 1, pp. 70-73, (Jan. 1979).
  • Winton, John M., “A novel way to capture solar energy”, Chemical Week, (May 1985).
  • Wu, “Design of a Reflective Color LCD Using Optical Interference Reflectors”, Asia Display '95, pp. 929-931, (Oct. 1995).
  • Butler et al., “An Embedded Overlay Concept for Microsystems Packaging,” IEEE Transactions on Advanced Packaging IEEE USA, vol. 23, No. 4, pp. 617-622, XP002379648 (2000).
  • Chiou et al., “A Novel Capacitance Control Design of Tunable Capacitor Using Multiple Electrostatic Driving Electrodes,” IEEE NANO 2001, M 3.1, Nanoelectronics and Giga-Scale Systems (Special Session), Oct. 29, 2001, pp. 319-324.
  • Chunjun Wang et al., “Flexible curcuit-based RF MEMS Switches,” MEMS. XP002379649 pp. 757-762, (Nov. 2001).
  • Goossen, “MEMS-based variable optical interference devices,” Optical MEMS, 2000 IEEE/LEDS Int'l. Conf. on Aug. 21-24, 2000, Piscatawny, NJ, Aug. 21, 2000, pp. 17-18.
  • Jerman et al., “Miniature Fabry-Perot Interferometers Micromachined in Silicon for Use in Optical Fiber WDM Systems,” Transducers, San Francisco, Jun. 24-27, 1991, Proceedings on the Int'l. Conf. on Solid State Sensors and Actuators, vol. CONF. 6, Jun. 24, 1991, pp. 372-375.
  • Joannopoulos et al., “Molding the Flow of Light,” Photonic Crystals. 1995.
  • Nagami et al., “Plastic Cell Architecture: Towards Reconfigurable Computing for General-Purpose,” Proc. IEEE Workshop on FPGA-based Custom Computing Machines, (1998).
  • Peerlings et al., “Long Resonator Micromachined Tunable GaAs-A1As Fabry-Perot Filter,” IEEE Photonics Technology Letters, IEEE Service Center, Piscatawny, NJ, vol. 9, No. 9, Sep. 1997, pp. 1235-1237.
  • Wu et al., “MEMS Designed for Tunable Capacitors,” Microwave Symposium Digest, 1998 IEEE MTT-S Int'l., Baltimore, MD, Jun. 7-12, 1998, vol. 1, pp. 127-129.
  • Zhou et al., “Waveguide Panel Display Using Electromechanical Spatial Modulators,” SID Digest, vol. XXIX, 1998.
  • European Search Report Application No. 05255693.3-2217, dated May 24, 2006.
  • European Search Report Application No. EP 05 25 5673 in 9 pages, dated Jan. 23, 2006.
  • International Search Report and Written Opinion of the International Searching Authority for PCT/US2005/005919 dated Aug. 24, 2005.
  • International Search Report Application No. PCT/US2005/026448, Dated Nov. 23, 2005.
  • International Search Report Application No. PCT/US2005/029820, Dated Dec. 27, 2005.
  • International Search Report Application No. PCT/US2005/030962, Dated Aug. 31, 2005.
  • International Search Report Application No. PCT/US2005/034465, Dated Sep. 23, 2005.
  • Austrian Search Report No. 140/2005, Dated Jul. 15, 2005.
  • Austrian Search Report No. 161/2005, Dated Jul. 15, 2005.
  • Austrian Search Report No. 162/2005, Dated Jul. 14, 2005.
  • Austrian Search Report No. 164/2005, Dated Jul. 4, 2005.
  • Austrian Search Report No. 150/2005, Dated Jul. 29, 2005.
  • Austrian Search Report No. 144/2005, Dated Aug. 11, 2005.
  • Austrian Search Report No. 66/2005, Dated May 9, 2005.
  • Fan et al., “Channel Drop Filters in Photonic Crystals,” Optics Express, vol. 3, No. 1, 1998.
  • Kim et al., “Control of Optical Transmission Through metals Perforated With Subwave-Length Hole Arrays,” Optic Letters, vol. 24, No. 4, Feb. 15, 1999, pp. 256-257.
  • Lin et al., “Free-Space Michromachined Optical Switches for Optical Networking,” IEEE Journal of Selected Topics in Quantum Electronics, vol. 5, No. 1m Jan./Feb. 1999, pp. 4-9.
  • Little et al., “Vertically Coupled Microring Resonator Channel Dropping Filter,” IEEE Photonics Technology Letters, vol. 11, No. 2, 1999.
  • Magel, “Integrated Optic Devices Using Micromachined Metal Membranes,” SPIE vol. 2686, 0-8194-2060-3/1996.
  • Science and Technology, The Economist, May 22, 1999, pp. 89-90.
  • ISR and WO for PCT/US2005/013462, filed Apr. 20, 2005.
  • Fork, et al., Chip on Glass Bonding Using StressedMetal™ Technology, SID 05 Digest, pp. 534-537, 2005.
  • Office Action issued Dec. 26, 2006 in ROC (Taiwan) App. No. 094114422.
  • IPRP for PCT/US05/013462 filed Apr. 20, 2005.
Patent History
Patent number: 7476327
Type: Grant
Filed: May 4, 2004
Date of Patent: Jan 13, 2009
Patent Publication Number: 20050249966
Assignee: IDC, LLC (Pleasanton, CA)
Inventors: Ming-Hau Tung (Santa Clara, CA), Brian James Gally (San Rafael, CA), Manish Kothari (Redwood City, CA), Clarence Chui (San Mateo, CA), John Batey (San Francisco, CA)
Primary Examiner: Allan Olsen
Attorney: Knobbe Martens Olson & Bear, LLP
Application Number: 10/839,329